/* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date:        15. February 2012
* $Revision: 	V1.1.0
*
* Project: 	    CMSIS DSP Library
* Title:		arm_cmplx_mag_q15.c
*
* Description:	Q15 complex magnitude.
*
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
*
* Version 1.1.0 2012/02/15
*    Updated with more optimizations, bug fixes and minor API changes.
*
* Version 1.0.10 2011/7/15
*    Big Endian support added and Merged M0 and M3/M4 Source code.
*
* Version 1.0.3 2010/11/29
*    Re-organized the CMSIS folders and updated documentation.
*
* Version 1.0.2 2010/11/11
*    Documentation updated.
*
* Version 1.0.1 2010/10/05
*    Production release and review comments incorporated.
*
* Version 1.0.0 2010/09/20
*    Production release and review comments incorporated.
* ---------------------------------------------------------------------------- */

#include "arm_math.h"

/**
 * @ingroup groupCmplxMath
 */

/**
 * @addtogroup cmplx_mag
 * @{
 */


/**
 * @brief  Q15 complex magnitude
 * @param  *pSrc points to the complex input vector
 * @param  *pDst points to the real output vector
 * @param  numSamples number of complex samples in the input vector
 * @return none.
 *
 * <b>Scaling and Overflow Behavior:</b>
 * \par
 * The function implements 1.15 by 1.15 multiplications and finally output is converted into 2.14 format.
 */

void arm_cmplx_mag_q15(
    q15_t* pSrc,
    q15_t* pDst,
    uint32_t numSamples)
{
	q31_t acc0, acc1;                              /* Accumulators */

#ifndef ARM_MATH_CM0

	/* Run the below code for Cortex-M4 and Cortex-M3 */
	uint32_t blkCnt;                               /* loop counter */
	q31_t in1, in2, in3, in4;
	q31_t acc2, acc3;


	/*loop Unrolling */
	blkCnt = numSamples >> 2u;

	/* First part of the processing with loop unrolling.  Compute 4 outputs at a time.
	 ** a second loop below computes the remaining 1 to 3 samples. */
	while(blkCnt > 0u) {

		/* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
		in1 = *__SIMD32(pSrc)++;
		in2 = *__SIMD32(pSrc)++;
		in3 = *__SIMD32(pSrc)++;
		in4 = *__SIMD32(pSrc)++;

		acc0 = __SMUAD(in1, in1);
		acc1 = __SMUAD(in2, in2);
		acc2 = __SMUAD(in3, in3);
		acc3 = __SMUAD(in4, in4);

		/* store the result in 2.14 format in the destination buffer. */
		arm_sqrt_q15((q15_t)((acc0) >> 17), pDst++);
		arm_sqrt_q15((q15_t)((acc1) >> 17), pDst++);
		arm_sqrt_q15((q15_t)((acc2) >> 17), pDst++);
		arm_sqrt_q15((q15_t)((acc3) >> 17), pDst++);

		/* Decrement the loop counter */
		blkCnt--;
	}

	/* If the numSamples is not a multiple of 4, compute any remaining output samples here.
	 ** No loop unrolling is used. */
	blkCnt = numSamples % 0x4u;

	while(blkCnt > 0u) {
		/* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
		in1 = *__SIMD32(pSrc)++;
		acc0 = __SMUAD(in1, in1);

		/* store the result in 2.14 format in the destination buffer. */
		arm_sqrt_q15((q15_t)(acc0 >> 17), pDst++);

		/* Decrement the loop counter */
		blkCnt--;
	}

#else

	/* Run the below code for Cortex-M0 */
	q15_t real, imag;                              /* Temporary variables to hold input values */

	while(numSamples > 0u) {
		/* out = sqrt(real * real + imag * imag) */
		real = *pSrc++;
		imag = *pSrc++;

		acc0 = (real * real);
		acc1 = (imag * imag);

		/* store the result in 2.14 format in the destination buffer. */
		arm_sqrt_q15((q15_t)(((q63_t) acc0 + acc1) >> 17), pDst++);

		/* Decrement the loop counter */
		numSamples--;
	}

#endif /* #ifndef ARM_MATH_CM0 */

}

/**
 * @} end of cmplx_mag group
 */
